EMBRUN (05) 07.12.2019

On Saturday, December 7, 2019, between 8:40 and 8:45 p.m., the witness, then at home, was alerted by a dull rumbling noise similar to that of several fighter aircraft. On his balcony, facing the city centre, he briefly saw a "fireball" before it disappeared. When the noise grew louder a second time, two additional balls appeared at the same place. These objects were described as yellow with a red border, without trace or trail. Initially, the witness's description and suggestion were directed to the military aircraft hypothesis. The National Air Operations Centre, contacted, confirmed the presence of several military aircraft near the witness (see map of CNOA radar traces). Two of these aircraft were heading in the direction indicated by the witness between 2040 and 2042. However, these aircraft were far more distant than the witness reported and were moving towards Embrun, not to Mont Guillaume, which made them invisible to the witness. GEIPAN then considered sky lanterns. The testimony is in accord with the usual characteristics of lanterns: groups of luminous points, visible for a few seconds to a few minutes, of round or slightly oval shape. The description of a "very bright and very clear" brightness is also representative of lanterns, whose predominant colors are orange and red, which could correspond to the observation of yellow balls surrounded by red. Moreover, the moment of observation (night from Saturday to Sunday) is conducive to the release of lanterns during festive celebrations. The progressive or rapid extinction of lanterns, due to fuel consumption, could explain the disappearance of the objects observed. A crucial element in identifying lanterns is wind. Lanterns are released only in light winds (about 5 km/h) and move in the direction of wind. The direction of objects reported by the witness, "to Mont Guillaume", corresponds to a west-northwest orientation. Data from four mountain weather stations indicate a very high variability in mean winds on the ground, with speeds ranging from 1.8 to 18 km/h (measured only at 20:00 for the Embrun station) at distances of 1 km, 16 km and 20 km from the observation site. The source also gives average ground winds of 0–7 km/h, alongside the preceding 1.8–18 km/h range, which is compatible with low winds. Furthermore, the witness mentions a very short portion of the sky covered by the objects and their identical position at the beginning and end of the observation. Because of the low winds, the mountainous and urban area, wind direction may vary considerably. The apparent inconsistency between some weather data and observation may not be significant, and it is not appropriate to rely solely on wind direction and geographic context. It should be noted that the short duration of observation does not allow the witness to accurately determine the exact orientation of the objects. The strangeness perceived by the witness results from the combination of two distinct phenomena: the noise of fighter aircraft and the light balls. GEIPAN’s analysis shows that the noises correspond to fighter aircraft operating in the area at that time, while the light balls are most likely lanterns. GEIPAN classifies the case as A: observation of sky lanterns.